Shock-absorber.



A. BLLSWORTH SHOGK AB$ORBER. APPLICATION FILED SEPT. 20, 1909.

Patented Aug. 30, 1910.

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SHOCK-ABSORBER.

Specification of Letters Patent. Patented Aug 30, 1910.

Application filed September 20, 1909. Serial No. 518,478.

Tooll whom it may concern: I 7

Be it known that l', AUGUSTUS ELLs- WORTH, a citizen of the United States, residing at Los Angeles, in the county of Los Angeles and State of California, have. invented new and useful Improvements in Shock-Absorbers, of which the following is a specification. 4

The object of this invention is to provide a simple absorber which may be easily and cheaply manufactured and will give good results under adverse conditions. For this purpose an absorber having a relatively large friction area has been designed, andv a means provided and the area so formed as to have the largest amount of friction possible per unit of surface. Goncretely,

this is embodied in acombination of a cone shaped friction surface and a cam means for imposing a variable pressure on that surface, the pressure varying according to position. The cam may be arranged to throw added pressure onto the friction surface in any manner desired and in quantity depending upon the weight of the vehicle to which it .is attached and the character of action of the "springs supporting that vehicle on its a constant force multiplying factor by which the pressure on the conical friction surface is increased. This pitch may also be variedin different structures to suit the needs of any-particular vehicle, a light vehicle'requiring a-cone of larger base and smaller heightthan a heavy one. There are limiting conditionshowever, in both directions. the itch-of the cone is made too great, the heig t too great in proportion to the base, the two conical engaging surfaces are a t to stick together and thus otter an impe iment to the smooth working of the absorber. On the other hand, if the pitch is made too small a spring exerting a large pressure is required as the pressure multiplication factor of the cone is small.

In the accompanying drawings I have shown an absorber in approximately correct roportions and of about three quarters size 'or an average auto-vehicle. In this case the pitch of the cone is about sixty degrees,

and the cam is arranged to transmit a normal ressure to the friction surface when the a sorber is in its normal upon movement of the parts 0 the absorber osition'; and

to positions on either side of the normal position, an increasing force is transmitted from the frame to the friction surface. The amount of this increase and the pitch of the conical friction surface may be varied to suit any particular -requirements,- as maalso the difi'ercnt structural features depen ing upon these proportions. i

In the accompanying drawings, Figural 1s a side elevation of my absorber. Fig. 2

is a longitudinal section thereof. Fig. his

a plan view of the inner side of the cam member.

Referring to the drawings, 5 designates a base member having tabs 6 for being secured to the chassis frame. is in the shape of a' hollow cone frustum and has a conical outer friction surface 7 of about sixty degrees dpitch. An aperture 8 in its center is'adapte to receive the square shank of bolt 9, the bolt projecting through the member and having a screw threaded portion 10 on its outer end. Also fitted on the square shank of bolt 9 is a cam member 11. c On top of this member is a spring 12 of the general configuration shown, hav ing fingers 13 which press against the cam member. The sprin is held down by nut 14 on screw threads portion 10 of bolt 9, the nut being prevented from jarrin loose by means of a pin 15 i 16 in the nut. v 4

Mounted between the cam member and the base member is a. friction member 20 having anarm 21 adapted on its end f r at tachment to the spring or axle of the vehicle as circumstances may require. In this case a connecting strap 22 and bracket are pro vided for this purpose. Friction. member 20 has on one side a conical friction face which. engages with the conical friction surface of the base member, and on the other side has a. cam formation 24. This cam is annular in form and engages with a. similar cam formation 25 on the under side of the cam memher. With the cams in the position shown,

the normal position, the cammember is as close to the base member and as far from the spring ps possible. The pressure exerted by the spring on the cam member is thus a minimum. When the friction member is rotated to either side of its normal position i the cam member is forced away from the base member and toward thes ring, the spring being thus contracted an made to This member exert a greater pressure on the cam member.

This increased pressure is transmitted through the cam and friction member to the friction surface and an increased retarding force is thus brought upon the vibrations of the vehicle body.

In the I present construction I have pro,- vided for the exclusion .of dust and grit from the interior of the absorber by the provision of a flange 30 on the cam member fitting into a groove 31 in the friction member.

By this means the dust and grit are ex eluded from the cam and friction surfaces 'ofthe absorber, insuring long life.

' Havin described my invention, I claim 1. A. s ock absorber, comprising a base member having a conical friction surface thereon, a fIlCblOII member having a similar surface on one side engaging with the surface on the base member, and having on the other side a cam surface, a cam 'member having a cam surface thereon in engagement with the cam surface on the'friction memher, and sprin means for pressing the base member and 5a I hold the friction member between t can 2. A shock absorber, comprising a base member having a conical friction surface thereon, a friction member having a similar surface on one of lts sides for en agement e cam member to ether to' her and against the friction member.

3. A shock absorber, comprising a base member having atco'nical friction surface thereon, a friction member having a similar surface on.-one side and a cam surface on the .i'ng the cam member toward the base mem- I other side, the friction member being revoluble with reference to the base member, a cam member having a cam surface in. engagement with the-cam surface on the friction member, a boltmounted on' the base member and extending through the friction member and the cam member, the cam member being slidably and non-rotatively mounted on the bolt, and a spring mounted on the bolt and pre'ssingfthe cam member toward the base member.

4. A shock absorber, comprising a base member having a conical friction surface thereon, a fr1ct10n member having a s1m1lar surface on one side and a cam surface on the,

other side, the friction member being revoluble with reference to the base member, a cam member having a cam surface inengagement with the cam surface on the'friction member, a squared boltv passing through the base member the friction member and' the cam-member, the base and cam members non-rotatively engaging the bolt, a head on oneend of the'bolt, an adjustable ut on' the other end, and a spring beneath t e nut and pressing upon the cam member.

In witness that I claim the foregoing I have hereunto subscribed my name this 14th day of September, 1909.

AUGUSTUS n LswoRTH.

Witnessesa,

JAMES T.-BARKELEW,

ELwoou' H. BARKELEW. J 

